Note that under threaded MPMs, some of the read/write accessors, will
be able to set values only before threads are spawned (i.e. before the
ChildInit phase).
Therefore if you are developing your application on the non-threaded
MPM, but planning to have it run under threaded mpm, you should not
use those methods to set values after the ChildInit phase.

The affected accessor methods are marked as such in their respective
documentation entries.

Apache2::ServerRec also provides auto-generated Perl interface for a
few other methods which aren't tested at the moment and therefore
their API is a subject to change. These methods will be finalized
later as a need arises. If you want to rely on any of the following
methods please contact the the mod_perl development mailing list so we can help each other take the steps necessary
to shift the method to an officially supported API.

META: this methods returns a vhost-specific Apache2::ServerAddr object,
which is not implemented at the moment. See the struct server_addr_rec
entry in httpd-2.0/include/httpd.h for more information. It seems that
most (all?) of the information in that record is available through
other APIs.